Tag: Mars

As I write this I am in Huntsville, Alabama at Space Camp! I’m here forRocketFest, a celebration of space with music, talks, and a Saturn V full of fun stuff. We’re doing this to raise money for the U.S. Space & Rocket Center Foundation.

I know, I’ve posted a few of these, but a new video came out showing the descent of Curiosity to the surface of Mars that’s worth a look.

YouTube user "hahahaspam" did a clever thing. The Mars Descent Imager (MARDI) is a camera that points straight down, past the rover, so engineers on Earth could later see the exact path Curiosity took on its way down to the Martian surface and also get an overview of the area. It took a series of images that were later put together to make various animations (see Related Posts below). The motion appears jerky because the camera only took about four pictures per second.

What hahahaspam did was interpolate between the frames, making the motion appear much more smooth. The animation he made is really quite wonderful:

Nice, huh? Interpolation is a math term that involves estimating the value of something between two measurements. A simple example involves someone running. You measure their progress: after one second they’ve traveled 2 meters, and after two seconds they’ve run 4 meters. How far did they get in 1.5 seconds?

Obviously, the answer is 3 meters. It may not be exact – a person’s running speed might change – but it’s probably close. There is a precise mathematical way to do interpolations like this, and that’s what hahahaspam did. Digital pictures are really just long strings of numbers, and video is the same thing except each pixel value changes with time. All you need to do is take two frames taken some time apart, then interpolate the value at each pixel for what it would be halfway between the time of the first frame and the second, and boom! You’ve made a video with twice the frame rate and the motion looks smoother.

It’s actually a lot harder than this in practice (rapid brightness or color changes makes this more difficult and less accurate, for example), but I hope this gives you the idea of how it works. The result in this case is pretty cool. Hahahaspam also created a side-by-side comparison of the original and interpolated videos, too, so you can see how they look together.

Very nice! And well done. I think it’s great that so many folks are so inspired by this that they want to play with the data. It really shows how much this has affected people.

The Curiosity rover is still going through its shake down phase, using new equipment and making sure all is well. A few days ago, engineers fired up its 100 mm camera – a telephoto that has a bit more zoom to it than the cameras from which we’ve been seeing pictures. They pointed it to the base of Mount Sharp, the big mountain in the center of its new home of Gale Crater. And what it saw is, simply, breath-taking:

Holy moley. That’s fantastic! [Click to barsoomenate.]

It looks a lot like rock formations I’ve seen in Arizona and Utah… but then, the geologic processes that formed this region are similar. At some point in the past it was flooded with water, and looking at the layering this happened many, many times. The sediments built up and then were worn away over the eons, forming this gorgeous striped sedimentary rock.

Inset here is part of the same scene with distances to various landmarks labeled [click to embiggen]. It looks like there’s the edge of a hill 230 meters away, and then it’s up, up, up, to a series of broad, eroded buttes 16 km away. That would be a fun day’s bike ride here on Earth, but it’s a long way for the rover.

But that is the destination. And it’s not so much the goal as the journey that’s important here. The geology of this region is pretty interesting, and should reveal a lot about the history of the area including how it interacted with water (and what kind of water it was; probably very salty).

These pictures are really exciting. The thing is, the first few times we sent landers to Mars they had to go to relatively boring places – not that any site on Mars is boring, but they had to be relatively flat and free of dangers to the terrestrial machines. Curiosity is the first rover we’ve sent to a place that has real honest-to-Ares geology. I mean, look at it! It’s like the Grand Canyon. But it’s on Mars.

In case you’re not getting enough Curiosity in your life, here are two videos, both showing the descent from the rover’s eye view. However, these are new and pretty different!

The first video shows the descent using the high-resolution images from the MARDI (Mars Descent Imager), which have been further cleaned up and sharpened. It’s truly magnificent! Make sure you set the video to hi-res and make it full screen:

The second video is really clever: it keeps the heat shield centered in the screen, so you can follow the entire fall of the shield down to its impact on the surface of Mars.

I’ve been a scientist a long time, and I’ve worked on astronomical and space imagery since I was in high school. I’ve used film I loaded, developed, and printed myself; I’ve used giant glass plates sprayed with film emulsion and hand-guided a telescope for hours; I’ve used a digital detector that was less than a megapixel and felt like it was the greatest invention ever; and I’ve had a hand in building a camera with three digital detectors that went on board Hubble. So I’ve watched as – and participated in – this revolution in astronomical imagery as it’s unfolded.

And I strongly suspect the single greatest thing about it is the power of pictures it puts into people’s hands. We have images taken by far-flung spacecraft beamed back to Earth at the speed of light, and then sent around the world in minutes by space agencies. From there space enthusiasts and professional filmmakers alike can take that vast archive of data and play with it, show different things, bring out details we at first hadn’t seen.

And we are seeing the results now, as we literally follow the rover down to Mars in high-def, or watch as an ejected piece of hardware plummets to the surface of an alien world.

I’ve said before, and it’ll always be true: The future! We are in you!

[The article below was originally posted on the BBC Future blog, and was titled "Will we ever… find life elsewhere in the universe?" I’m reposting it here because, oddly, the BBC page is only readable for people outside the UK! It has to do with the BBC rights and all that. But they gave me permission to post it here, and since I thought it was fun and provocative, I figure y’all would like it. Enjoy.]

Will we ever… find life in space?

One of the reasons I love astronomy is that it doesn’t flinch from the big questions. And one of the biggest is: are we alone?

Another reason I love astronomy: it has a good shot at answering this question.

Even a few decades ago hard-headed realists pooh-poohed the idea of aliens. But times change, and so does science. We’ve accumulated enough data that makes the question less far-fetched than it once was, and I’m starting to think that the question isn’t "Will we find life?" but rather "Which method will find it first?"

There are three methods that, to me, are the front-runners for finding life on other worlds. And I have an idea as to which one may find it first.

Life on Mars?

The first method follows the principle that when you’re looking for something, it’s best to start close to home.
We know of one planet that has life: Earth. So it makes sense to look for other places with Earth-like conditions: that is, liquid water, oxygen in the air, nutrients for growth, and so on.

The most obvious place to look is Mars. At first glance it appears dry, cold and dead. But if you can see past that, things start to look up. The polar caps, for example, have lots of frozen water, and we’ve directly seen ice at lower latitudes on the Red Planet as well – meteorite impacts have left behind shiny craters, digging up fresh ice from below the surface.

Several Mars rovers and landers have uncovered tantalising evidence that liquid water might flow just beneath the surface, but we still lack any conclusive evidence. However, if you broaden your timescale a bit, there is excellent evidence that in the past – perhaps a billion years or so ago – our neighbouring planet had oceans of liquid water and thicker air. In fact, conditions were pretty good to develop life as we know it even before it popped up here on Earth.

It’s entirely possible that life got a toehold (or pseudopod hold) there long ago, and died out. If that’s the case, we may yet find fossils in the Martian rocks. Again, there’s no conclusive evidence yet, but we’ve literally barely scratched the surface there. Now that it has successfully landed on Mars, we have the exciting possibility that the plutonium-powered, car-sized Curiosity rover will soon use its on-board laser and other tools to crack open and examine rocks in the Gale Crater, which were laid down billions of years ago in the presence of liquid water.

And Mars isn’t the only possibility in our solar system. Liquid water exists inside Saturn’s moon Enceladus, where geysers of liquid water erupt from deep canyons at its south pole. Energised by the gravitational tug of the giant ringed planet itself, the interior of Enceladus may be a vast ocean of liquid water even while the surface is frozen over. That doesn’t guarantee we’ll ever find alien fish swimming that moon’s seas, of course. But it’s an interesting place to look.

Europa, a moon of Jupiter, almost certainly has an undersurface ocean as well. If you relax your constraints even more, Saturn’s moon Titan has lakes of liquid methane and ethane on its surface, too. The chemistry for life would be different there – it’s a rather chilly -180C on the surface – but it’s not impossible to suppose life might arise there too.

Finding out whether this is the case means getting up close and personal. We’re doing that for Mars; however, the likes of Europa and Enceladus may have to wait a decade or four.

Phone home

But maybe we don’t have to go anywhere. Instead, we might be able to sit here and wait for alien beings (of whatever form) to message us.

Just a few minutes ago, engineers at JPL here on Earth commanded the Mars Curiosity rovers to make its first test drive! The rover rolled a few meters, stopped and took a picture of its progress:

[Click to enaresenate.]

Wow! This image was taken by the left NAVCAM (NAVigation CAMera) on Curiosity at 15:00:53 UTC (there’s a matching one by the right NAVCAM, too, and there’s already an anaglyph that’s been made). You can easily see where the wheels have disturbed the Martian surface, and where the rover made a bit of a turn as well.

I’m also fond of this picture, taken just a few minutes later at 15:03:56 UTC, also by the left NAVCAM:

Seeing the rover in the picture itself, ironically, brings home the idea that this machine is far, far away from home.

Note the sundial at the top right; you can see the shadow of the rover moving as time elapses. If you watch the ground you can see the perspective of the camera changing a bit as the rover rocks, too; the wheel movement is causing the rover to move slightly with each frame of the sequence.

In more good news, yesterday the engineers extended the 2-meter long boom arm. The arm has a set of tools at the end, including a camera, a scoop, a drill, a sifter, and a spectrometer (to determine the composition of samples). So it looks like Curiosity is about ready to start poking around Mars!

The background image is from the Curiosity NAVCAM and shows the region around Greedo Coronation (you can see the rover’s shadow on the left). The zoomed region in the circle shows the area of the rock targeted by the laser just before the laser hit it (you can see the edge of the rock on the right side of the zoom). The final zoom at the top shows the pit zapped into the rock by the laser pulse.]

This isn’t mad science! It’s cool science.

OK, well, hot science.

Here’s the deal: when atoms and molecules absorb energy, they can re-emit that energy as light. The nifty part is, each type of substance emits a different color of light, making it possible to identify them. This is called spectroscopy, and we use it in astronomy all the time. Many objects like gas clouds and stars emit light naturally. We just have to observe them and pick out the signatures of the different chemicals in them.

For a Martian rock, though, we need to dump some energy into it to excite those substances. And that’s why Curiosity has a laser on board. It can zap a rock with a short, intense pulse of laser light, and the rock will respond by glowing. A spectrometer – a camera that can separate light into individual colors – then observes the glow, and scientists back home can see what the rock’s made of. It’s like DNA-typing or fingerprinting the rock, but from 150 million kilometers away.

Reports are the laser worked perfectly, blasting away at the rock with 30 one-megaWatt pulses (lasting 5 nanoseconds each!) in a span of about 10 seconds. Scientists are poring over the results now, and hopefully we’ll hear more about this soon.

Some amazing videos are still coming out from NASA about the Mars Curiosity rover’s descent to the planet’s surface. This one is blink-and-you’ll-miss-it-but-still-totally-freaking-cool: the heat shield slamming into the surface of Mars and blurting out a cloud of dust:

Not only that, but the high-resolution pictures from the Mars Descent Imager (MARDI – a camera pointing down that took shots as the rover was lowered to the ground by the sky crane) have been sent back to Earth, and Spaceflight101 made this incredible video from them:

I love love LOVE the swirling dust set into motion at 00:41 by the sky crane’s rocket thrusters once it got close enough to the ground. And you can see when one of the rover’s wheels snaps down into place as well!

These videos are honestly astonishing to me. When I was a kid we had to wait forever to get (sometimes pretty cruddy) images from our space probes. Now we get flippin’ color video of hardware slamming down and/or settling gently onto another planet! The pace of technological advancement may be most popular when it comes to things like cell phones and computers, but as a scientist I can tell you that the impact on our ability to do research has been profound almost beyond comprehension. Digital cameras that can be lofted into space, or made to see great gaping sections of the sky, or into the ultraviolet and infrared, or with high enough resolution to see incredibly small features on other planets… or all of the above. This technology has, quite literally, opened up whole new worlds to us.

It’s a fantastic time to be alive. And to have Curiousity.

Tip o’ the lens cap to BABloggee Dave Jerrard for the tip about the MARDI video.

Because the planets are so terribly old, and impacts so rare, I still have this (very slight) prejudice that craters are old too. The Moon was bombarded billions of years ago, and the craters on Earth are mostly so old that they’ve eroded away. Heck, even a "new" crater like the one in Arizona is tens of thousands of years old.

Getting the age of a crater can be tricky. But sometimes it’s so easy it’s literally a matter of keeping your eyes on one spot. Like this spot on Mars:

That image (highly color enhanced; click here for a grayscale version) shows a crater seen by a camera on the Mars Reconnaissance Orbiter in 2011. We can tell it’s young because it’s still surrounded by the ejecta blanket; material that blasted out of the crater and settled around it. That stuff tends to erode away (or get covered in dust and sand by Martian winds) relatively quickly.

But in this case, we know just how young it is: it wasn’t seen in images taken of the same spot by a camera on board the Odyssey Mars probe… in 2009! In other words, this crater is less than three years old!

That’s so cool. And it speaks to the power of having multiple, sustained missions to other worlds. Things change. If we take one picture and then walk away, we’ll miss a lot.